Revert "[Qt] memory leak in WebCore::FontCache::getLastResortFallbackFont"

This causes the browser example to crash on startup on 32bit x86.

This reverts commit 25e8da88b2008e62c62206bddc815229761a0fb2
Task-number: QTBUG-32879

Change-Id: I38fb03f7fec5f9a197613d16cc59761b780ec49a
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>